[PATCH v5 3/7] ARM: dts: Exynos542x/5800: add CPU OPP properties

Javier Martinez Canillas javier at osg.samsung.com
Thu Dec 10 19:25:37 PST 2015


Hello Viresh,

On 12/11/2015 12:16 AM, Viresh Kumar wrote:
> On 10-12-15, 17:58, Bartlomiej Zolnierkiewicz wrote:
>> diff --git a/arch/arm/boot/dts/exynos5422-cpus.dtsi b/arch/arm/boot/dts/exynos5422-cpus.dtsi
>> index b7f60c8..9a5131d 100644
>> --- a/arch/arm/boot/dts/exynos5422-cpus.dtsi
>> +++ b/arch/arm/boot/dts/exynos5422-cpus.dtsi
>> @@ -20,8 +20,10 @@
>>  	device_type = "cpu";
>>  	compatible = "arm,cortex-a7";
>>  	reg = <0x100>;
>> +	clocks = <&clock CLK_KFC_CLK>;
>>  	clock-frequency = <1000000000>;
>>  	cci-control-port = <&cci_control0>;
>> +	operating-points-v2 = <&cpu1_opp_table>;
>>  };
> 
> Why do you need to update this file? This file is included by
> exynos5422-odroidxu3-common.dtsi, which already inherits cpus nodes
> from exynos5800.dtsi (which inherits exynos5420.dtsi).
> 
> i.e. operating-points-v2 should already be set.
>

The problem is that the big and LITTLE cores have different ordering per SoCs:

- Exynos5420 and Exynos5800: cpu0-3 (Cortex-A15) and cpu4-7 (Coretx-A7)
- Exynos5422: cpu0-3 (Cortex-A7) and cpu4-7 (Cortex-A15)

So the OPP tables are set in this DTSI file, to prevent the OPP tables
in the Exynos5422 to be inverted for the cluster 0 and 1.

Best regards,
-- 
Javier Martinez Canillas
Open Source Group
Samsung Research America



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